The overall project will determine the structure of proteins from Mycoplasma genitalium and Mycoplasma pneumoniae. These structures will enhance the database of protein folds, and will be interpreted to suggest possible functions for the proteins. This component of the overall project will apply solution NMR methods to determine structures of small proteins from these organisms using multinuclear multidimensional methods. Sets of experiments will be designed which are optimized for assignment of resonances from proteins with specific linewidths. Methods for automated analysis of data (determination of backbone and sidechain assignments, and assignment of NOE crosspeaks) will be implemented, and extended to optimize throughput. Proteins homologous to M.g. and M.p. but from thermophilic organisms will be evaluated fro NMR work. Data collection at higher temperature is improved due to decreased linewidths, enhancing data quality and hence the ability to automate analysis. The interpretation of structures determined in terms of fold classification and function will be done in collaboration with other members of the project. NMR will also be applied to evaluation of proteins for crystallography, attempting to identify flexible regions, and comains which may hinder crystallography, attempting to identify flexible regions, and domains which may hinder crystallization.